Parameters and Variables
This section describes parameters and variables.
User-Defined Variables
Any variable defined by a programmer is a user defined variable. User-defined variable names
Must start with letters
Can contain only letters or digits
Are often in capital letters to differentiate them from UNIX commands
Variables are assigned values using the assignment operator, =, as follows:
VAR=value
Here, VAR is the name of the variable and value is the value you want to assign to it.
Variables are unset using the unset command as follows:
unset var1 ... varN
Here var1 … varN are the names of the variables to unset.
Variable Substitution
The value stored in a variable can be accessed using the $ operator as follows:
$VAR
Here VAR is the ...
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